Geschützte und gefährdete Pflanzen, Tiere und Landschaften des Landes Sachsen-Anhalt : zu den Abbildungen 2. und 3. Umschlagseite

Die Weißflügel- und Weißbart-Seeschwalbe konnten nun auch für Sachsen-Anhalt als Brutvögel nachgewiesen werden. In der unteren Havelniederung im Biosphärenreservat „Mittelelbe“ (BR ME) wurden am 06.06.2007 neben nahrungssuchenden Weißflügel-Seeschwalben auch Nistmaterial tragende und brütende Weißbart-Seeschwalben festgestellt. Am nächsten Tag erfolgte eine nochmalige Kontrolle des Gebietes, während dieser auch noch das Brutvorkommen der Weißflügel-Seeschwalbe nachgewiesen werden konnte

Realization of a classical counterpart of a scalable design for adiabatic quantum computation

We implement a classical counterpart of a scalable design for adiabatic quantum computation. The key element of this design is a coupler providing controllable coupling between two bistable elements (in our case superconducting rings with a single Josephson junction playing the role of a classical counterpart of superconducting flux qubits) The coupler is also a superconducting ring with a single Josephson junction that operates in the non-hysteretic mode. The flux coupling between two bistable rings can be controlled by changing the magnetic flux through the coupler. Thereby, the coupling can be tuned from ferromagnetic trough zero to to anti-ferromagnetic.Comment: 3 pages, 3 figures v2: extended discussion experimental result

Current carrier lifetime in doping superlattice crystals

It is shown, that the lifetime of nonequilibrium current carriers in the luminescence process in doping superlattice structures changes in a wide range with increasing the excitation level of the crystal. Two effects are important, i. e., (a) lowdimensional character of the carrier distribution and (b) change in the overlap of electron and hole wave functions. At low excitation, non-radiative recombination can play principal cause in the stabilization of the effective lifetime of current carriers. At high excitation, the effective lifetime of current carriers approaches the value in the bulk crystal. The major attention was given to the compensated GaAs doping superlattices with i-layers (n-i-p-i crystals) and to the structures with no i-layers (n-p-n-p structures). The layer thickness of n-, p-, and i-type were 20, 40, or 60 nm and the concentrations of the dopants Te and Zn made up to 1018 cm3. Photoluminescence spectra and the decay time of the spontaneous emission intensity in the superlattices were measured at the temperature interval from 1 1 to 300 K. The influence of u-particle irradiation and thermal annealing on the luminescence spectra and the carrier lifetime was also investigate

Ectomycorrhizal influence on the dynamics of sesquiterpene release by Tricholoma vaccinum

Tricholoma vaccinum is an ectomycorrhizal basidiomycete with high host specificity. The slow-growing fungus is able to produce twenty sesquiterpenes, including α-barbatene, sativene, isocaryophyllene, α-cuprenene, β-cedrene, ß-copaene, 4-epi-α-acoradiene, and chamigrene in axenic culture. For the three major compounds, Δ(6)-protoilludene, β-barbatene, and an unidentified oxygenated sesquiterpene (m/z 218.18), changed production during co-cultivation with the ectomycorrhizal partner tree, Picea abies, could be shown with distinct dynamics. During the mycorrhizal growth of T. vaccinum–P. abies, Δ(6)-protoilludene and the oxygenated sesquiterpene appeared at similar times, which warranted further studies of potential biosynthesis genes. In silico analyses identified a putative protoilludene synthesis gene, pie1, as being up-regulated in the mycorrhizal stage, in addition to the previously identified, co-regulated geosmin synthase, ges1. We therefore hypothesize that the sesquiterpene synthase pie1 has an important role during mycorrhization, through Δ(6)-protoilludene and/or its accompanied oxygenated sesquiterpene production